import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * @param str string字符串 待判断的字符串
     * @return bool布尔型
     */
    public boolean judge(String str) {
        // write code here
        int front = 0;
        int rear = str.length() - 1;
        while (front < rear) {
            if (str.charAt(front) != str.charAt(rear)) return false;
            front++;
            rear--;
        }
        return true;
    }

    public int sqrt(int x) {
        // write code here
        int a = 0;
        while (a <= x) {
            if (a * a == x) return a;
            if (a * a > x) return a - 1;
            a++;
        }
        return 0;
    }
}